Answer:
yes
Explanation:
Answer:
yes
Explanation:
Humans inhale oxygen and breath out carbon dioxide.
How many moles of KBr are present in 500 ml of a 0.8 M KBr solution?
1. 1.6
2. .4
3. .625
4. 625
5. .0016
Answer:
2) 0.4 mol
Explanation:
Step 1: Given data
Volume of the solution (V): 500 mLMolar concentration of the solution (M): 0.8 M = 0.8 mol/LStep 2: Convert "V" to L
We will use the conversion factor 1 L = 1000 mL.
500 mL × 1 L/1000 mL = 0.500 L
Step 3: Calculate the moles of KBr (solute)
The molarity is the quotient between the moles of solute (n) and the liters of solution.
M = n/V
n = M × V
n = 0.8 mol/L × 0.500 L = 0.4 mol
The face-centered cubic unit cell describing the structure of an ionic compound has an edge length of 207 pm. The lattice points of the unit cell are occupied by anions, and the cations are small enough so that the anions are in contact along the diagonal of the face of the unit cell. What is the ionic radius of the anion (in picometers)
Answer:
73.2 pm
Explanation:
"The anions make contact along the diagonal of the face of the unit cell, so the diagonal of the face is equal to 4 ionic anion radii. By letting r represent the ionic radius of the anion, d represent the diagonal of the face of the unit cell, and x represent the edge length, then d=4r and
d^2=x^2+x^2= 2x^2
By substituting 4r for d, the second equation becomes
(4r)^2=(2)x^2
Solving this equation for r shows that
r=(x–√2)/4
Since the edge length x is 207 pm, the ionic radius of the anion is
r= ((207 pm) X [tex]\sqrt{2}[/tex])/4=73.2 pm
Notice that the formulae used to describe atomic radii include constants with exact values. Therefore, these values do not constrain the number of significant figures."
The ionic radius of the anion in the FCC unit cell where anions are in contact along the diagonal of the face of the unit cell is 73.1pm.
What is ionic radius?Ionic radius is the distance between the center of the atom and the outermost part.
As in the question it is given that anions are in contact along the diagonal of the face of the unit cell, so the length of the diagonal is represented as: d = 4r, where
r = ionic radius
Length of edge i.e. a = 207 pm (given)
Two adjacent edges and diagonal of a FCC unit cell makes a right angle triangle, by using pythagoras theorem we can write as:
a² + a² = d²
2a² = (4r)²
2a²/16 = r²
2(207)²/16 = r²
85,698/16 = r²
0r r = 73.18 pm
Hence, 73.18 pm is the ionic radius of the anion.
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PLEASE HELP IMMEDIATE WORTH 10 POINTS
Fill in the blank with the word or phrase that best completes the statement or answers the question. The scientific name for a plant that reproduces with flowers is a(n)
Answer:
the scientific name is Angiosperms
Explanation:
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A granulated cylinder was filled to 30.0 mL with liquid. An unknown metal cylinder having a mass of 60.27 g was submerged in the liquid. The final volume of the liquid level was 45.2 mL.
Answer:
Explanation:
A graduated cylinder was filled to 30.0 mL with a liquid. An unknown metal cylinder having a mass of 60.27 g was submerged in the in the liquid. The final volume of the liquid level was 45.2 mL.
a. Calculate the density of the unknown metal cylinder.
b. The density of the liquid is 0.899 g/mL. What is the mass of the liquid in the graduated cylinder?
GIVING 21 POINTS AWAY PLEASE HELP ME WITH BOTH QUESTIONS ASAP!!!!
11. This metalloid has 6 valence electrons and 6 electron shells. I 12. This element has the same number of electrons as a Sulfur ion. SH 10:3 3/3 W
Answer:
11. Polonium.
12. Argon.
Explanation:
In Chemistry, electrons can be defined as subatomic particles that are negatively charged and as such has a magnitude of -1.
Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.
11. Polonium: this metalloid has 6 valence electrons and 6 electron shells. It has 84 electrons with 6 shell structure 2, 8, 18, 32, 18, 6.
Therefore, polonium has the following electronic configuration;
Polonium = 1s² 2s² 2p² 3s² 3p6 3d10 4s² 4p6 4d10 5s² 5p6 4f¹⁴ 5d10 6s² 6p⁴
12. Argon: this element has the same number of electrons as a Sulfur ion. It has 18 electrons.
Mercury(II) oxide decomposes to form mercury and oxygen, like this:
2Hg (l) + O2 (g) → 2HgO (s)
At a certain temperature, a chemist finds that a reaction vessel containing a mixture of mercury(II) oxide, mercury, and oxygen at equilibrium has the following composition:
compound amount
Hg 14.7g
O2 13.4g
HgO 17.8g
Calculate the value of the equilibrium constant for this reaction. Round your answer to significant digits. Clears your work. Undoes your last action. Provides information about entering answers.
Solution :
For the reaction given :
[tex]$\text{2Hg}_{(l)}+\text{O}_2_{(g)} \rightarrow \text{2HgO}_{(s)}$[/tex]
Thus we know that the equilibrium constant [tex]$K_c$[/tex] contains aqueous an dgas species only.
∴ [tex]$K_c=\frac{1}{[O_2]}$[/tex] ............(1)
Now at the equilibrium, an amount of the 13.4 g of oxygen was found in the vessel of 6.9 liters. For determining the concentration of the oxygen gas, we use :
[tex]$[O_2]= \frac{n_{O_2}}{V_{soln}}$[/tex] ................... (2)
Here, [tex]$n_{O_2}$[/tex] = no. of moles of oxygen gas (mol)
[tex]$V_{soln}$[/tex] = volume of solution (L)
Therefore the number of moles of the oxygen gas is calculated by directly using the molecular weight (31.9988 g/mol) as the conversion factor.
∴ [tex]$n_{O_2}= 13.4 \ g \times \frac{\text{1 mol}}{31.9988 \ g}$[/tex]
= 0.418 mol
Now substituting the known values in (2), we can find the equilibrium concentration of the oxygen gas :
[tex]$[O_2] =\frac{0.418 \ \text{mol}}{6.9 \ \text{L}}$[/tex]
= 0.0605 M
Therefore substituting the result in (1), the equilibrium constant for the reaction is :
[tex]$K_c=\frac{1}{0.0605}$[/tex]
= 16.52
Mario’s teacher asked him to explain the important role of the sun in the water cycle. Which response would be correct?
which property is a property of water
Answer: Polarity, Boiling and Freezing Points, Specific Heat Capacity, Density, Surface Tension, Heat of Vaporization and Vapor Pressure, Capillary Action, Solid State (Ice), Liquid State (Liquid Water), Gas State (Steam),
Explanation: Water molecules are polar, so they form hydrogen bonds. This gives water unique properties, such as a relatively high boiling point, high specific heat, cohesion, adhesion, and density.
What are the details of the chemical structure of methylisothiazolinone (MIT)?
Which example indicates that a chemical change has occurred? *
1 point
A. When two aqueous solutions are mixed, a precipitate is formed.
B. As ammonium nitrate dissolves in water causes the temperature to decrease.
C. Alcohol evaporates when left in an open container.
D. Water is added to blue copper(II) chloride solution. The resulting mixture if lighter blue in color.
Answer:
A. When two aqueous solutions are mixed, a precipitate is formed.
Explanation:
The precipitate (a solid substance that falls from the liquid) is the result of a chemical reaction taking place between the liquids.
The other three answer choices are indicative of physical changes (temperature change, phase change, color change).
When two aqueous solutions are mixed, a precipitate is formed indicates that a chemical change has occurred.
Hence, option A is correct answer.
What is Chemical change ?Chemical change are those changes in which substance changes chemical composition. These changes are permanent changes. In chemical change new substances formed and in chemical change substances can not get back into its original form. It is irreversible change.
What is Physical change ?Physical changes are those changes in which substance changes physical properties only. Properties like temperature, pressure, shape, color, size, state (solid, liquid and gas). These changes are temporary in nature. In physical change no new substances formed. It is reversible change.
Now, check all the options one by one:
Option (A): When two aqueous solutions are mixed, a precipitate is formed is a chemical change. Since precipitation indicate a chemical reaction (that is double displacement reaction).
Option (B): As ammonium nitrate dissolved in water causes the temperature to decrease is a physical change because heat energy is absorbed here and it is a endothermic reaction.
Option (C): Alcohol evaporates when left in an open container is a physical change because evaporation is a physical change as it changes the state from liquid state to gas state.
Option (D): Water is added to blue copper (II) chloride solution. The resulting mixture if lighter blue in color is a physical change as properties like change in color is physical change.
Thus, from above conclusion we can say that When two aqueous solutions are mixed, a precipitate is formed indicates that a chemical change has occurred.
Hence, option A is correct answer.
Learn more about physical and chemical change here: https://brainly.com/question/17166994
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Which element best conducts electricity?
argon
copper
nitrogen
oxygen
Answer:
I think it is copper
Explanation:
.........................
Answer:
copper
Explanation:
While performing a neutralization reaction, Jonna added 27.55 mL of 0.144 M H2SO4 to 43.84 mL of 0.316 M KOH. How many moles of OH- are unreacted in the solution after the neutralization is complete?
Answer:
5.916x10⁻³ mol OH⁻
Explanation:
The reaction that takes place is:
H₂SO₄ + 2KOH → K₂SO₄ + 2H₂OFirst we calculate the added moles of each reagent, using the given volumes and concentrations:
H₂SO₄ ⇒ 0.144 M * 27.55 mL = 3.967 mmol H₂SO₄KOH ⇒ 0.316 M * 43.84 mL = 13.85 mmol KOHNow we calculate how many KOH moles reacted with 3.967 mmol H₂SO₄:
3.967 mmol H₂SO₄ * [tex]\frac{2mmolKOH}{1mmolH_2SO_4}[/tex] = 7.934 mmol KOHFinally we calculate how many OH⁻ moles remained after the reaction
13.85 mmol - 7.934 mmol = 5.916 mmol OH⁻5.916 mmol / 1000 = 5.916x10⁻³ mol OH⁻Calculate the molarity of 29.25 grams of NaCI in 2.0 liters of solution
Answer:
[NaCl(aq)] = 0.25M
Explanation:
Molarity = moles solute / volume of solution in liters
moles NaCl in 29.25 grams = 29.25g/58g·mol⁻¹ = 0.5043 mole
Molarity = 0.5043 mole NaCl / 2 Liters = 0.2555M ≅ 0.25M (2 sig-figs)
need help whoever answers will be awarded branliest answer
Answer:
1.used to seperate solids from liquids, and is a act of pouring a mixture onto a membrane this allows the passage of liquid and results in the collection of a solid
2. the solution would passed through without losing and solids
3 would allow them to dry or on further hearing decompose
Explanation:
Which of the following is a true statement?
A. Erosion due to wind-blown sand is a process of chemical weathering.
B. due to wind-blown sand is a process of geological weathering.
C. Erosion due to wind-blown sand is a process of biological weathering.
D.Erosion due to wind-blown sand is a process of mechanical weathering.
Answer:
C
Explanation:
Wind is geological therefore it is geological weathering
hi, if your looking for extra points (50+) and brainiest here is ur chance, answer this question correctly plz
Answer:
Answer is B
Explanation:
It's not A because we're boiling only water.
It's not C because the last dot for 2 cups ends at 70 min while the last dot for 4 cups ends at 90 min.
It's not D because water boils at around 100 C, as shown in the graph. The highest dot for both 2 cups and 4 cups were about the same near 100 C.
The graph shows that 4 cups of water is able to retain heat more (higher heat capacity), so it takes more time for water to cool down than 2 cups of water.
A force of 10 N pulls an object to the right, and a force of 7 N pulls to the left, what is the net force
Answer:
2 N
Explanation:
how many atoms are in 4.67 grams of sample of silicon
a furnace is thermal energy
A. True
B. False
Answer: true
Explanation:
Thermal efficiency of process heating equipment
how to convert n butylbenzene to benzoic acid
Answer:
When an alkyl benzene is heated with strong oxidizing asgents like acidic or alkline KMnO4
or acidified K2Cr2O7
, etc. gives aromatic carboxyllic acid. The alkyl side chain gets oxidised to −COOH
group irrespective of the size of the chain.
Explanation:
Thermal energy that encounters greenhouse gases cannot escape the atmosphere? Yes or no
Answer:
Yes
Explanation:
The point of greenhouse gases is that it absorbs and emits radiant energy within the thermal infrared range and causes it to be trapped.
I NEED AWNSER ASAP What forms as a result of the wind's frictional force on water?
deep sea currents that move in a path opposite to the wind currents
surface currents that move in a path similar to the wind currents
surface currents that move in a path opposite to the wind currents
deep sea currents that move in a path similar to the wind currents (the sub is science)
Answer:
2 no. is the answer surface currents that move in a path opposite to the wind currents
Answer:
no.2 is the answer of your question
I need help ASAP plz :)
Draw Lewis structures for the following compounds/ions. Decide if the compound/ion listed can satisfy the octet rule (duet rule for H), if so choose Satisfies Octet Rule from the drop down menu. If the compound/ion cannot satisfy the octet rule for one of the atoms in the formula, choose one of the following three reasons why; Too many valence electrons (more than eight), Too few valence electrons (fewer than eight), or Odd
The question is incomplete, the complete question is;
Draw Lewis structures for the following compounds/ions.
Decide if the compound/ion listed can satisfy the octet rule (duet rule for H), if so choose Satisfies Octet Rule from the drop down menu.
If the compound/ion cannot satisfy the octet rule for one of the atoms in the formula, choose one of the following three reasons why;
Too many valence electrons (more than eight), Too few valence electrons (fewer than eight), or Odd # of valence electrons.
Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons KrCl2
Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons PCl3
Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons BeH2
Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons NO3-
Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons SeO22-
Satisfies Octet Rule Too many valence electrons Too few valence electrons Odd # of valence electrons SO2
Answer:
See explanation
Explanation:
Let us consider the number of valence electrons in each of the species. This will let us know whether the specie satisfies the octet rule or not.
KrCl2 has a total of 22 valence electrons. This implies that there are too many valence electrons hence the compound does not satisfy the octet rule.
For PCl3, there are 26 valence electrons. This compound satisfies the octet rule.
For BeH2, there are four valence electrons. This number of valence electrons is too few hence BeH2 does not satisfy the octet rule.
NO3^- has 24 valence electrons and is represented using resonance structures. Its resonance structures show that the specie satisfies the octet rule.
SeO2^2- has 20 valence electrons. This specie satisfies the octet rule.
SO2 has 18 valence electrons and is represented by resonance structures which satisfy the octet rule.
How many moles of ethanol are produced starting with 500.g glucose?
C6H12O6 → 2 C2H5OH + 2 CO2
5.55 mol C₂H₅OH
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TablesMolesStoichiometry
Using Dimensional AnalysisAnalyzing Reactions RxNExplanation:Step 1: Define
[RxN - Balanced] C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂
[Given] 500. g C₆H₁₂O₆ (Glucose)
[Solve] moles C₂H₅OH (Ethanol)
Step 2: Identify Conversions
[RxN] 1 mol C₆H₁₂O₆ → 2 mol C₂H₅OH
[PT] Molar mass of C - 12.01 g/mol
[PT] Molar Mass of H - 1.01 g/mol
[PT] Molar Mass of O - 16.00 g/mol
Molar Mass of C₆H₁₂O₆ - 6(12.01) + 12(1.01) + 6(16.00) = 180.18 g/mol
Step 3: Stoichiometry
[DA] Set up conversion: [tex]\displaystyle 500 \ g \ C_6H_{12}O_6(\frac{1 \ mol \ C_6H_{12}O_6}{180.18 \ g \ C_6H_{12}O_6})(\frac{2 \ mol \ C_2H_5OH}{1 \ mol \ C_6H_{12}O_6})[/tex][DA} Multiply/Divide [Cancel out units]: [tex]\displaystyle 5.55001 \ mol \ C_2H_5OH[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
5.55001 mol C₂H₅OH ≈ 5.55 mol C₂H₅OH
Which of the following is the correct decreasing order of hydrogen ions concentrations?
Answer: A> B> C > D> E
Explanation:
pH or pOH is the measure of acidity or alkalinity of a solution.
pH is calculated by taking negative logarithm of hydrogen ion concentration.
[tex]pH=-\log [H^+][/tex]
a) Solution A: pH =2
[tex][H^+]=10^{-2}[/tex]
b) Solution B: pH =5
[tex][H^+]=10^{-5}[/tex]
c) Solution C: pH = 7
[tex][H^+]=10^{-7}[/tex]
d) Solution D: pH = 8
[tex][H^+]=10^{-8}[/tex]
e) Solution E: pH =13
[tex][H^+]=10^{-13}[/tex]
Thus the decreasing order of hydrogen ion concentration is A> B> C > D> E
who are called anthropologist?
Answer: A person engaged in the practice of anthropology. Anthropology is the study of aspects of humans within past and present societies. Social anthropology, cultural anthropology and philosophical anthropology study the norms and values of societies.
Explanation: I HOPE THIS HELPS U AND ANSWERS UR QUESTION!!! Stay safe and healthy!
What is the molar mass of H2CO3?
(Molar mass of H = 1.0079 g/mol; C = 12.010 g/mol; O = 15.999 g/mol)
Answer:
molar mass of H2CO3 = 72.0228
Answer:
62.02 g/mol
Explanation:
Took the test and got it right. if you have enough faith in brainly youll choose the right answer
Looking at the map, what ideas do you have about why the trash is "trapped" in this location
Answer:
Due to the circulation of the wind and water the trash will continue to go around in a circle thus causing it to be trapped there.